The proposed work employs unit electrophysiology to study neuronal coding of taste input in n. tractus solitarius, pontine taste area and ventral forebrain structures (amygdala and substantia innominata) in the anesthetized rabbit. The organization of projections from PTA to forebrain structures in the rabbit will be studied by means of electrophysiological and neuroanatomical techniques. The information gained on "static" properties of ventral forebrain processing of taste input, as defined in the anesthetized preparation, will be utilized in studying electrophysiologically more "dynamic" aspects of taste processing in these structures in the behaving preparation. Through use of a conditioning paradigm employed in the context of intra-oral injections of each of the four basic types of taste stimuli, we hope to examine interrelations between conditional and taste-related unconditional modes of reaction and to assess motor and motivational relationships of unit activity. Other pilot work will explore electrophysiologically the potential role of locus coeruleus in such taste-mediated behavior.